Which combination of features characterizes tetralogy of Fallot prenatally?

Prepare for the Fetal Echocardiography Test. Utilize flashcards and multiple-choice questions that come with hints and explanations. Ace your exam preparation!

Multiple Choice

Which combination of features characterizes tetralogy of Fallot prenatally?

In tetralogy of Fallot, the heart’s outflow tract and septation are misaligned in a way that creates a distinctive prenatal imaging pattern: the aorta overrides a large VSD, there is obstruction of the right ventricular outflow tract (RVOT), and the pulmonary arteries are relatively small due to reduced flow to the lungs. This combination—overriding aorta, RVOT obstruction, a subpulmonary/perimembranous VSD, and a small pulmonary artery—captures the classic TOF anatomy seen on fetal echocardiography. The malalignment of the infundibular septum pushes the aorta to ride over the VSD, and the RVOT obstruction limits blood going to the lungs, so the pulmonary arteries remain underdeveloped. The VSD is typically large, located subpulmonic or perimembranous, which complements the overriding aorta. Other scenarios described, such as normal anatomy, intact VSD, or a relatively large pulmonary artery, do not fit the TOF pattern. A coarctation feature may occur with TOF but represents a different or additional lesion rather than the standard prenatal signature of TOF.

In tetralogy of Fallot, the heart’s outflow tract and septation are misaligned in a way that creates a distinctive prenatal imaging pattern: the aorta overrides a large VSD, there is obstruction of the right ventricular outflow tract (RVOT), and the pulmonary arteries are relatively small due to reduced flow to the lungs. This combination—overriding aorta, RVOT obstruction, a subpulmonary/perimembranous VSD, and a small pulmonary artery—captures the classic TOF anatomy seen on fetal echocardiography. The malalignment of the infundibular septum pushes the aorta to ride over the VSD, and the RVOT obstruction limits blood going to the lungs, so the pulmonary arteries remain underdeveloped. The VSD is typically large, located subpulmonic or perimembranous, which complements the overriding aorta.

Other scenarios described, such as normal anatomy, intact VSD, or a relatively large pulmonary artery, do not fit the TOF pattern. A coarctation feature may occur with TOF but represents a different or additional lesion rather than the standard prenatal signature of TOF.

More practice questions